Fail-Safe Function Block F_Brake_Test; Introduction - Siemens Simatic Manual

Fail-safe function blocks for storage and retrieval machines

3.8 Fail-safe function block F_BRAKE_TEST

3.8.1

Introduction

The fail-safe function block F_BRAKE_TEST is used to control the SBT drive function to test a motor
holding brake or an external brake.
The specified torque and the test profiles are saved in the SI part of the drive in the Safe Brake Test
(SBT). When requested, the block handles the automatic coordination of the parameterized test se-
quences.
The function of two independent brakes is tested by establishing a torque against the brake that is
closed.
If the brake test is unsuccessful, the block supports a retraction logic with SDI and SLS. This means
that only travel with reduced velocity is possible, and for an application, e.g. hoisting gear, only down-
wards.
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S7-Distributed Safety/SIMATIC Safety - fail-safe function blocks for storage and retrieval machines